Lead investigator E. Kathleen Adams at Emory University in Atlanta said it is estimated almost 23 percent of women enter pregnancy as smokers and more than half of those women smoke during pregnancy.
Researchers at Emory University and the Centers for Disease Control and Prevention examined cigarette smoking among 225,445 women with live births from 2000 to 2005 in 29 states plus New York City.
Data on smoking status -- pre-pregnancy smoking; quitting during pregnancy; and remaining quit four months after delivery -- were merged with cigarette price data, including federal, state and local cigarette excise taxes, data on state tobacco control spending for the period, and the existence of full or partial bans of worksite or restaurant smoking.
"This is one of the first studies of pregnant women's smoking in the new era of more restrictive state tobacco control policies," Adams said in a statement. "We found that a $1.00 increase in cigarette taxes increases the quit rate among pregnant women from 44.1 percent to 48.9 percent, a sizable effect. Moreover, tax policies appear to be effective in keeping these women from relapsing in the first few months postpartum, and the implementation of a full workplace smoke-free policy also increases quits."
The study was published online in advance of the July print issue of the American Journal of Preventive Medicine.